1. Field of the Invention
The present invention relates to a semiconductor device, a circuit having the device, and a correlation calculation apparatus, a signal converter, and a signal processing system utilizing the circuit. More particularly, the semiconductor device is one that allows parallel signal processing, a circuit having the device, and a correlation calculation apparatus, a signal converter including an A/D (analog-to-digital) converter or a D/A (digital-to-analog) converter, and a signal processing system utilizing the circuit.
2. Related Background Art
In recent years, along with an increase in signal processing speed, it has become important to realize low-cost arithmetic operation apparatuses that can process a very large volume of data at high speed. Of these apparatuses, the above demand is even stronger for a correlation apparatus used in motion detection for dynamic images, high-precision analog-to-digital and digital-to-analog converters, and the like.
Since a technique such as a spread spectrum (SS) communication requires high-speed, multiple input signal processing on the GHz order in some cases, a demand for parallel processing of a large volume of data is becoming stronger in addition to further increases in processing speed and precision.
Conventionally, when such functions are realized using a semiconductor integrated circuit, parallel arithmetic operations are attained using a plurality of semiconductor chips so as to attain high-speed arithmetic operation processing. However, since the use of the plurality of semiconductor chips results in an increase in circuit area, an attempt for realizing a one-chip circuit using the latest micropatterning rule has been made.
Despite such attempt, since the conventional circuit arrangement basically has a large circuit scale, it requires a considerably large circuit scale even using the latest micropatterning rule, and circuit integration on one chip involves difficulty.
As is well known, when the number of bits of a signal to be processed increases, the circuit scale of such a chip sharply increases. For example, the circuit scale increases in proportion to the square of the number of bits to be operated on.
Therefore, as the number of bits increases, the manufacturing cost of the apparatus increases, and the apparatus undesirably has a circuit scale that cannot be realized in practice. For example, a motion detection chip of suitable for the MPEG2 method, which has been proposed as a compression/expansion method of dynamic images, has not been integrated on a single chip yet.